The world's largest canal lock is at Ijmuiden, a small port city in the Port of Amsterdam, The Netherlands. Dutch King Willem-Alexander dedicated the sea lock. The sea lock in Ijmuiden is 500 meters long and 70 meters broad. The major infrastructure project's construction began in 2016 and was supposed to be completed by 2019. It also exceeded the initial budget by roughly €300 million.

The Ijmuiden lock was built to allow large, contemporary cargo ships to approach Amsterdam's port. The construction is also low enough that ships would no longer need to wait for a good level of water to approach the canal. With a height of about 9 meters above the sea tier, the building also acts as flood security.

The IJmuiden sealock is among the world's largest. The Velsen lock, which is located in the municipality of Velsen, was inaugurated on January 26, 2022, in the sight of King Willem-Alexander of the Netherlands.